Rewrite retrieval of resolved classes.
Use ClassLinker::VisitClasses() instead of walking over dex
cache type arrays. The old technique relies on the dex cache
holding references to all resolved classes, an assumption
that we're going to break soon.
Test: m test-art-host-run-test-595-profile-saving
Bug: 30627598
Change-Id: Icae71f53b5a33ff931d83aa8d44cc182889f26da
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index e65672a..abd35f1 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -19,6 +19,7 @@
#include <algorithm>
#include <deque>
#include <iostream>
+#include <map>
#include <memory>
#include <queue>
#include <string>
@@ -8479,6 +8480,81 @@
}
}
+class GetResolvedClassesVisitor : public ClassVisitor {
+ public:
+ GetResolvedClassesVisitor(std::set<DexCacheResolvedClasses>* result, bool ignore_boot_classes)
+ : result_(result),
+ ignore_boot_classes_(ignore_boot_classes),
+ last_resolved_classes_(result->end()),
+ last_dex_file_(nullptr),
+ vlog_is_on_(VLOG_IS_ON(class_linker)),
+ extra_stats_(),
+ last_extra_stats_(extra_stats_.end()) { }
+
+ bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) {
+ if (!klass->IsProxyClass() &&
+ !klass->IsArrayClass() &&
+ klass->IsResolved() &&
+ !klass->IsErroneousResolved() &&
+ (!ignore_boot_classes_ || klass->GetClassLoader() != nullptr)) {
+ const DexFile& dex_file = klass->GetDexFile();
+ if (&dex_file != last_dex_file_) {
+ last_dex_file_ = &dex_file;
+ DexCacheResolvedClasses resolved_classes(dex_file.GetLocation(),
+ dex_file.GetBaseLocation(),
+ dex_file.GetLocationChecksum());
+ last_resolved_classes_ = result_->find(resolved_classes);
+ if (last_resolved_classes_ == result_->end()) {
+ last_resolved_classes_ = result_->insert(resolved_classes).first;
+ }
+ }
+ bool added = last_resolved_classes_->AddClass(klass->GetDexTypeIndex());
+ if (UNLIKELY(vlog_is_on_) && added) {
+ const DexCacheResolvedClasses* resolved_classes = std::addressof(*last_resolved_classes_);
+ if (last_extra_stats_ == extra_stats_.end() ||
+ last_extra_stats_->first != resolved_classes) {
+ last_extra_stats_ = extra_stats_.find(resolved_classes);
+ if (last_extra_stats_ == extra_stats_.end()) {
+ last_extra_stats_ =
+ extra_stats_.emplace(resolved_classes, ExtraStats(dex_file.NumClassDefs())).first;
+ }
+ }
+ }
+ }
+ return true;
+ }
+
+ void PrintStatistics() const {
+ if (vlog_is_on_) {
+ for (const DexCacheResolvedClasses& resolved_classes : *result_) {
+ auto it = extra_stats_.find(std::addressof(resolved_classes));
+ DCHECK(it != extra_stats_.end());
+ const ExtraStats& extra_stats = it->second;
+ LOG(INFO) << "Dex location " << resolved_classes.GetDexLocation()
+ << " has " << resolved_classes.GetClasses().size() << " / "
+ << extra_stats.number_of_class_defs_ << " resolved classes";
+ }
+ }
+ }
+
+ private:
+ struct ExtraStats {
+ explicit ExtraStats(uint32_t number_of_class_defs)
+ : number_of_class_defs_(number_of_class_defs) {}
+ uint32_t number_of_class_defs_;
+ };
+
+ std::set<DexCacheResolvedClasses>* result_;
+ bool ignore_boot_classes_;
+ std::set<DexCacheResolvedClasses>::iterator last_resolved_classes_;
+ const DexFile* last_dex_file_;
+
+ // Statistics.
+ bool vlog_is_on_;
+ std::map<const DexCacheResolvedClasses*, ExtraStats> extra_stats_;
+ std::map<const DexCacheResolvedClasses*, ExtraStats>::iterator last_extra_stats_;
+};
+
std::set<DexCacheResolvedClasses> ClassLinker::GetResolvedClasses(bool ignore_boot_classes) {
ScopedTrace trace(__PRETTY_FUNCTION__);
ScopedObjectAccess soa(Thread::Current());
@@ -8486,63 +8562,12 @@
std::set<DexCacheResolvedClasses> ret;
VLOG(class_linker) << "Collecting resolved classes";
const uint64_t start_time = NanoTime();
- ReaderMutexLock mu(soa.Self(), *Locks::dex_lock_);
- // Loop through all the dex caches and inspect resolved classes.
- for (const ClassLinker::DexCacheData& data : GetDexCachesData()) {
- if (soa.Self()->IsJWeakCleared(data.weak_root)) {
- continue;
- }
- ObjPtr<mirror::DexCache> dex_cache = soa.Decode<mirror::DexCache>(data.weak_root);
- if (dex_cache == nullptr) {
- continue;
- }
- const DexFile* dex_file = dex_cache->GetDexFile();
- const std::string& location = dex_file->GetLocation();
- const size_t num_class_defs = dex_file->NumClassDefs();
- // Use the resolved types, this will miss array classes.
- const size_t num_types = dex_file->NumTypeIds();
- VLOG(class_linker) << "Collecting class profile for dex file " << location
- << " types=" << num_types << " class_defs=" << num_class_defs;
- DexCacheResolvedClasses resolved_classes(dex_file->GetLocation(),
- dex_file->GetBaseLocation(),
- dex_file->GetLocationChecksum());
- size_t num_resolved = 0;
- std::unordered_set<dex::TypeIndex> class_set;
- CHECK_EQ(num_types, dex_cache->NumResolvedTypes());
- for (size_t i = 0; i < num_types; ++i) {
- ObjPtr<mirror::Class> klass = dex_cache->GetResolvedType(dex::TypeIndex(i));
- // Filter out null class loader since that is the boot class loader.
- if (klass == nullptr || (ignore_boot_classes && klass->GetClassLoader() == nullptr)) {
- continue;
- }
- ++num_resolved;
- DCHECK(!klass->IsProxyClass());
- DCHECK(klass->IsResolved());
- if (klass->IsErroneousResolved()) {
- continue;
- }
- ObjPtr<mirror::DexCache> klass_dex_cache = klass->GetDexCache();
- if (klass_dex_cache == dex_cache) {
- CHECK_LT(klass->GetDexClassDefIndex(), num_class_defs);
- class_set.insert(klass->GetDexTypeIndex());
- }
- }
-
- if (!class_set.empty()) {
- auto it = ret.find(resolved_classes);
- if (it != ret.end()) {
- // Already have the key, union the class type indexes.
- it->AddClasses(class_set.begin(), class_set.end());
- } else {
- resolved_classes.AddClasses(class_set.begin(), class_set.end());
- ret.insert(resolved_classes);
- }
- }
-
- VLOG(class_linker) << "Dex location " << location << " has " << num_resolved << " / "
- << num_class_defs << " resolved classes";
+ GetResolvedClassesVisitor visitor(&ret, ignore_boot_classes);
+ VisitClasses(&visitor);
+ if (VLOG_IS_ON(class_linker)) {
+ visitor.PrintStatistics();
+ LOG(INFO) << "Collecting class profile took " << PrettyDuration(NanoTime() - start_time);
}
- VLOG(class_linker) << "Collecting class profile took " << PrettyDuration(NanoTime() - start_time);
return ret;
}
diff --git a/runtime/dex_cache_resolved_classes.h b/runtime/dex_cache_resolved_classes.h
index f53ca4a..bebdf0d 100644
--- a/runtime/dex_cache_resolved_classes.h
+++ b/runtime/dex_cache_resolved_classes.h
@@ -44,6 +44,10 @@
return dex_location_.compare(other.dex_location_);
}
+ bool AddClass(dex::TypeIndex index) const {
+ return classes_.insert(index).second;
+ }
+
template <class InputIt>
void AddClasses(InputIt begin, InputIt end) const {
classes_.insert(begin, end);
